Star Formation Activity of Galaxies Undergoing Ram Pressure Stripping in the Virgo Cluster

TL;DR

This study investigates how ram pressure stripping affects star formation in Virgo cluster galaxies, finding no significant enhancement but clear evidence of overall quenching as stripping progresses.

Contribution

Introduces a new galaxy classification scheme combining HI content and phase space location to trace stripping stages and assess star formation activity.

Findings

No clear enhancement in star formation during early stripping stages

Star formation activity generally decreases with increased ram pressure stripping

Galaxy classification scheme effectively identifies different stripping stages

Abstract

We study galaxies undergoing ram pressure stripping in the Virgo cluster to examine whether we can identify any discernible trend in their star formation activity. We first use 48 galaxies undergoing different stages of stripping based on HI morphology, HI deficiency, and relative extent to the stellar disk, from the VIVA survey. We then employ a new scheme for galaxy classification which combines HI mass fractions and locations in projected phase space, resulting in a new sample of 365 galaxies. We utilize a variety of star formation tracers, which include g - r, WISE [3.4] - [12] colors, and starburstiness that are defined by stellar mass and star formation rates to compare the star formation activity of galaxies at different stripping stages. We find no clear evidence for enhancement in the integrated star formation activity of galaxies undergoing early to active stripping. We are instead able to capture the overall quenching of star formation activity with increasing degree of ram pressure stripping, in agreement with previous studies. Our results suggest that if there is any ram pressure stripping induced enhancement, it is at best locally modest, and galaxies undergoing enhancement make up a small fraction of the total sample. Our results also indicate that it is possible to trace galaxies at different stages of stripping with the combination of HI gas content and location in projected phase space, which can be extended to other galaxy clusters that lack high-resolution HI imaging.